A 41-year-old Florida mother of three was killed by her estranged husband on Thursday, NBC Miamireports.

Miami-Dade police say the husband approached Tania Adams and her 28-year-old male coworker at the Isles at Oasis community clubhouse and began shooting. After he killed Adams, he turned the gun on himself.

Though still in the beginning stages of an investigation, authorities believe it began with some sort of dispute.

“Preliminary investigation is letting us know that perhaps there was an argument. There was some type of dispute where a 51-year-old male produced a firearm, shot the female that was inside the clubhouse, shot the second victim that was transported and then, from what it appears, he shot himself,” said Detective Alvaro Zabaleta.

Adams’ sister told NBC that the male coworker, who was also shot, was friends with her sister and tried to protect her. According to police, he was transported to Jackson Memorial Hospital, where he is listed in critical but stable condition. The family has set up a GoFundMe page to help cover funeral costs.